Process for making a liquid fabric softening composition

ABSTRACT

There is provided a process for preparing a liquid softening composition comprising a fabric softener, a nonionic alkoxylated stabilizing agent, and a dye component, whereby the resulting softening composition exhibits effective freeze-thaw recovery properties and good dye homogeneity.

FIELD OF THE INVENTION

The present invention relates to a process for preparing a dyecontaining softening composition having effective freeze-thaw recoveryproperties.

BACKGROUND OF THE INVENTION

Fabric softening products are known in the art to provide effectivesoftness to the treated fabrics. However, a problem encountered uponstorage at low temperature, i.e. at sub 0° C. temperature, is thefreezing of the product which, when placed at higher temperaturesresults in a product which does not recover to a uniform dispersion withacceptable flow characteristics.

Accordingly, it is an object of the invention to provide a fabricsoftening product which has effective freeze-thaw recovery.

One solution to fulfill such need is described in GB-1,098,793 with theuse of sulphate salts of fatty amines in fabric softening compositions.

Still another solution is described in EP-A-0,507,478 which provides themixing and melting of the cationic fabric softener with a nonionicstabilising agent before dispersing it in water. However, a problemencountered with such a process is that processing equipment such ashigh shear mixers are needed so that the resulting cost of theformulation is increased.

Accordingly, it is also an object of the invention to provide a fabricsoftening product which only necessitates minimal processing equipment.

It has been observed that without high shear during the processing of afabric softening product, the formation of dye speckles arises, whilstwith high shear the formation of undispersed dye particles in the fabricsoftening product is avoided.

Accordingly, the formulator of a softening composition is faced with thedual challenge of formulating a softening composition which has good dyehomogeneity, without the need for a high shear mixing equipment.

The Applicant has now found that the addition of the dye componenttogether with a nonionic alkoxylated surfactant to the finished coldsoftening product fulfills such needs.

Indeed, application of the dye and nonionic alkoxylated surfactant tothe cold finished product is made by simple mixing. The compositionobtained results in an homogenous dispersion.

An advantage of the invention is that for resulting fabric softeningproducts in diluted form made by the invention process, less mechanicalshear is required compared to products made by mixing the fabricsoftener and nonionic before dispersion in water. Not to be bound bytheory, it is believed that the nonionic surfactant micellizes the dyeand subsequently forms mixed vesicles with the softener active. In thismanner the dye is efficiently dispersed and the product acquires goodfreeze thaw recovery.

SUMMARY OF THE INVENTION

The present invention relates to a process for making a liquid fabricsoftening composition which comprises the steps of:

a)-mixing and heating the fabric softener active and optional additivesto form a melt;

b)-dispersing the melt in water;

c)-cooling the resulting dispersion to below the Krafft temperature ofthe softener active before adding a dye and a nonionic alkoxylatedstabilising agent.

In another aspect, the present invention encompasses the use of anonionic alkoxylated stabilising agent in liquid fabric softeningcompositions as a freeze-thaw recovery agent.

Still in another aspect, the present invention encompasses the use of anonionic alkoxylated stabilising agent to homogenise the dye in liquidfabric softening compositions.

DETAILED DESCRIPTION OF THE INVENTION

Nonionic alkoxylated surfactant

A nonionic alkoxylated stabilising surfactant is an essential componentof the process invention. Suitable nonionic surfactants for use hereininclude addition products of ethylene oxide with fatty alcohols, fattyacids, fatty amines, etc. Optionally, addition products of propyleneoxide with fatty alcohols, fatty acids, fatty amines may be used.

Suitable compounds are surfactants of the general formula:

R²—Y—(C₂H₄O)_(z)—C₂H₄OH

wherein R² is selected from the group consisting of primary, secondaryand branched chain alkyl and/or acyl hydrocarbyl groups; primary,secondary and branched chain alkenyl hydrocarbyl groups; and primary,secondary and branched chain alkyl- and alkenyl-substituted phenolichydrocarbyl groups; said hydrocarbyl groups preferably having ahydrocarbyl chain length of from 8 to 20, preferably from 10 to 18carbon atoms. More preferably the hydrocarbyl chain length is from 12 to18 carbon atoms. In the general formula for the ethoxylated nonionicsurfactants herein, Y is —O—, —C(O)O—, —C(O)N(R)—, or —C(O)N(R)R—, inwhich R, when present, is R² or hydrogen, and z is at least 5,preferably at least 8.

The nonionic surfactants herein are characterised by an HLB(hydrophilic-lipophilic balance) of from 7 to 20, preferably from 8 to15. Of course, by defining R² and the number of ethoxylate groups, theHLB of the surfactant is, in general, determined. However, it is to benoted that the nonionic ethoxylated surfactants useful herein containrelatively long chain R² groups and are relatively highly ethoxylated.While shorter alkyl chain surfactants having short ethoxylated groupsmay possess the requisite HLB, they are not as effective herein.

Examples of nonionic surfactants follow. The nonionic surfactants ofthis invention are not limited to these examples. In the examples, theinteger defines the number of ethoxyl (EO) groups in the molecule.

a. Straight-Chain, Primary Alcohol Alkoxylates

The tri-, penta-, hepta-ethoxylates of dodecanol, and tetradecanol areuseful surfactants in the context of this invention. The ethoxylates ofmixed natural or synthetic alcohols in the “coco” chain length range arealso useful herein. Commercially available straight-chain, primaryalcohol alkoxylates for use herein are available under the tradenameMarlipal® 24/70, Marlipal 24/100, Marlipal 24/150 from Huls, andGenapol® C-050 from Hoechst.

b. Straight-Chain, Secondary Alcohol Alkoxylates

The tri-, penta-, hepta-ethoxylates of 3-hexadecanol, 2-octadecanol,4-eicosanol, and 5-eicosanol are useful surfactants in the context ofthis invention. A commercially available straight-chain secondaryalcohol ethoxylate for use herein is the material marketed under thetradename Tergitol 15-S-7 from Union Carbide, which comprises a mixtureof secondary alcohols having an average hydrocarbyl chain length of 11to 15 carbon atoms condensed with an average 7 moles of ethylene oxideper mole equivalent of alcohol.

c. Alkyl Phenol Alkoxylates

Suitable alkyl phenol alkoxylates are the polyethylene oxide condensatesof alkyl phenols, e.g., the condensation products of alkyl phenolshaving an alkyl or alkenyl group containing from 6 to 20 carbon atoms ina primary, secondary or branched chain configuration, preferably from 8to 12 carbon atoms, with ethylene oxide, the said ethylene oxide beingpreferably present in amounts equal to 3 to less than 9 moles ofethylene oxide per mole of alkyl phenol. The alkyl substituent in suchcompounds may be derived from polymerized propylene, diisobutylene,octane, and nonane.

Examples of this type of nonionic surfactants include Triton N-57® anonyl phenol ethoxylate (5EO) from Rohm & Haas, Dowfax® 9N5 from Dow andLutensol® AP6 from BASF.

d. Olefinic Alkoxylates

The alkenyl alcohols, both primary and secondary, and alkenyl phenolscorresponding to those disclosed immediately hereinabove can beethoxylated and used as surfactants.

Commercially available olefinic alkoxylates for use herein are availableunder the tradename Genapol O-050 from Hoechst.

e. Branched Chain Alkoxylates

Branched chain primary and secondary alcohols which may be availablefrom the well-known “OXO” process or modification thereof can beethoxylated. Particularly preferred among these ethoxylates of theprimary OXO alcohols are the surfactants marketed under the nameLutensol by BASF or Dobanol by the Shell Chemicals, U.K., LTD. Thepreferred Dobanols are primary alcohols with hydrocarbyl groups of 9 to15 carbon atoms, with the majority having a hydrocarbyl group of 13carbon atoms. Particularly preferred are Dobanols with an average degreeof ethoxylation of 3 to less than 9, and preferably 5 on the average.

An example of this type of material is an aliphatic alcohol ethyleneoxide condensate having from 3 to less than 9 moles of ethylene oxideper mole of aliphatic alcohol, the aliphatic alcohol fraction havingfrom 9 to 14 carbon atoms. Other examples of this type of nonionicsurfactants include certain of the commercially available Dobanol®,Neodol® marketed by Shell or Lutensol® from BASF. For example Dobanol®23.5 (C12-C13 EO5), Dobanol® 91.5 (C9-C11 EO 5) and Neodol 45 E5.

Other suitable nonionic alkoxylated surfactants are alkyl aminesalkoxylated with at least 5 alkoxy moieties. Typical of this class ofcompounds are the surfactants derived from the condensation of ethyleneoxide with an hydrophobic alkyl amine product. Preferably thehydrophobic alkyl group, has from 6 to 22 carbon atoms. Preferably, thealkyl amine is alkoxylated with 10 to 40, and more preferably 20 to 30alkoxy moieties.

Example of this type of nonionic surfactants are the alkyl amineethoxylate commercially available under the tradename Genamin fromHoechst. Suitable example for use herein are Genamin C-100, GenaminO-150, and Genamin S-200.

Still other suitable type of nonionic surfactant among this class arethe N,N′,N′-polyoxyethylene (12)-N-tallow 1,3 diaminopropanecommercialised under the tradename Ethoduomeen T22 from Akzo, andSynprolam from ICI.

The above ethoxylated nonionic surfactants are useful in the presentprocess invention alone or in combination, and the term “nonionicsurfactant” encompasses mixed nonionic surface active agents.

Preferred nonionic surfactants for use herein are the nonionicsurfactants commercially available under the tradenames Marlipal 24/100,Marlipal 24/150, Genapol O-050, and Dobanol 91.5.

The nonionic surfactant will preferably be added in an amount of 0.05%to 5% by weight, preferably from 0.1% to 0.5% by weight of the finishedfabric softening composition.

The Dye Component

The dye is an essential component of the invention. Hence, by mixed thedye together with the nonionic alkoxylated surfactants and subsequentlyincorporating it into the cold finished product, it has been observedthat the formation of dyes speckles which occurs by incorporation of thedyes into the molten fabric softening product is suppressed and/orreduced by the process of the invention.

Preferred dye components are the water-soluble dye such as described inEP 754749.

Preferably, the dye is a water soluble dye system characterised in thatthe dye system comprises a dye selected from the group consisting of:

1. Quinoline Yellow 70 with color index no. 47005;

2. Tartrazine XX90 with color index no. 19140;

3. Orange RGL90 with color index no. 15985;

4. Ponceau 4RC82 with color index no. 16255;

5. Blue AE85 with color index no. 42090;

6. Patent Blue V85V50 with color index no. 42051; and

7. mixtures thereof.

The dye will preferably be added in an amount of 1 ppm to 200 ppm byweight, preferably from 5 ppm to 100 ppm by weight of the finishedfabric softening composition.

The finished fabric softening composition conventionally comprises acationic fabric softener and optional additives.

Fabric Softener

Typical levels of incorporation of the softening compound in thesoftening composition are of from 1% to 80% by weight, preferably from5% to 75%, more preferably from 15% to 70%, and even more preferablyfrom 19% to 65%, by weight of the composition.

The fabric softener compound is preferably selected from a cationic,nonionic, amphoteric or anionic fabric softening component. Typical ofthe cationic softening components are the quaternary ammonium compoundsor amine precursors thereof as defined hereinafter.

A)-Quaternary Ammonium Fabric Softening Active Compound

(1) Preferred quaternary ammonium fabric softening active compound havethe formula

or the formula:

wherein Q is a carbonyl unit having the formula:

each R unit is independently hydrogen, C₁-C₆ alkyl, C₁-C₆ hydroxyalkyl,and mixtures thereof, preferably methyl or hydroxy alkyl; each R¹ unitis independently linear or branched C₁₁-C₂₂ alkyl, linear or branchedC₁₁-C₂₂ alkenyl, and mixtures thereof, R² is hydrogen, C₁-C₄ alkyl,C₁-C₄ hydroxyalkyl, and mixtures thereof; X is an anion which iscompatible with fabric softener actives and adjunct ingredients; theindex m is from 1 to 4, preferably 1; the index n is from 1 to 4,preferably 2.

An example of a preferred fabric softener active is a mixture ofquaternized amines having the formula:

wherein R is preferably methyl; R¹ is a linear or branched alkyl oralkenyl chain comprising at least 11 atoms, preferably at least 15atoms. In the above fabric softener example, the unit —O₂CR¹ representsa fatty acyl unit which is typically derived from a triglyceride source.The triglyceride source is preferably derived from tallow, partiallyhydrogenated tallow, lard, partially hydrogenated lard, vegetable oilsand/or partially hydrogenated vegetable oils, such as, canola oil,safflower oil, peanut oil, sunflower oil, corn oil, soybean oil, talloil, rice bran oil, etc. and mixtures of these oils.

The preferred fabric softening actives of the present invention are theDiester and/or Diamide Quaternary Ammonium (DEQA) compounds, thediesters and diamides having the formula:

wherein R, R¹, X, and n are the same as defined herein above forformulas (1) and (2), and Q has the formula:

These preferred fabric softening actives are formed from the reaction ofan amine with a fatty acyl unit to form an amine intermediate having theformula:

wherein R is preferably methyl, Q and R¹ are as defined herein before;followed by quaternization to the final softener active.

Non-limiting examples of preferred amines which are used to form theDEQA fabric softening actives according to the present invention includemethyl bis(2-hydroxyethyl)amine having the formula:

methyl bis(2-hydroxypropyl)amine having the formula:

methyl(3-aminopropyl)(2-hydroxyethyl)amine having the formula:

methyl bis(2-aminoethyl)amine having the formula:

triethanol amine having the formula:

di(2-aminoethyl)ethanolamine having the formula:

The counterion, X(⁻) above, can be any softener-compatible anion,preferably the anion of a strong acid, for example, chloride, bromide,methylsulfate, ethylsulfate, sulfate, nitrate and the like, morepreferably chloride or methyl sulfate. The anion can also, but lesspreferably, carry a double charge in which case X(⁻) represents half agroup.

Tallow and canola oil are convenient and inexpensive sources of fattyacyl units which are suitable for use in the present invention as R¹units. The following are non-limiting examples of quaternary ammoniumcompounds suitable for use in the compositions of the present invention.The term “tallowyl” as used herein below indicates the R¹ unit isderived from a tallow triglyceride source and is a mixture of fatty acylunits. Likewise, the use of the term canolyl refers to a mixture offatty acyl units derived from canola oil.

Table II

Fabric Softener Actives

N,N-di(tallowyl-oxy-ethyl)-N,N-dimethyl ammonium chloride;

N,N-di(canolyl-oxy-ethyl)-N,N-dimethyl ammonium chloride;

N,N-di(tallowyl-oxy-ethyl)-N-methyl, N-(2-hydroxyethyl)ammoniumchloride;

N,N-di(canolyl-oxy-ethyl)-N-methyl, N-(2-hydroxyethyl)ammonium chloride;

N,N-di(2-tallowyloxy-2-oxo-ethyl)-N,N-dimethyl ammonium chloride;

N,N-di(2-canolyloxy-2-oxo-ethyl)-N,N-dimethyl ammonium chloride

N,N-di(2-tallowyloxyethylcarbonyloxyethyl)-N,N-dimethyl ammoniumchloride;

N,N-di(2-canolyloxyethylcarbonyloxyethyl)-N,N-dimethyl ammoniumchloride;

N-(2-tallowoyloxy-2-ethyl)-N-(2-tallowyloxy-2-oxo-ethyl)-N,N-dimethylammonium chloride;

N-(2-canolyloxy-2-ethyl)-N-(2-canolyloxy-2-oxo-ethyl)-N,N-dimethylammonium chloride;

N,N,N-tri(tallowyl-oxy-ethyl)-N-methyl ammonium chloride;

N,N,N-tricanolyl-oxy-ethyl)-N-methyl ammonium chloride;

N-(2-tallowyloxy-2-oxoethyl)-N-(tallowyl)-N,N-dimethyl ammoniumchloride;

N-(2-canolyloxy-2-oxoethyl)-N-(canolyl)-N,N-dimethyl ammonium chloride;

1,2-ditallowyloxy-3-N,N,N-trimethylammoniopropane chloride; and

1,2-dicanolyloxy-3-N,N,N-trimethylammoniopropane chloride;

and mixtures of the above actives.

Other examples of quaternay ammoniun softening compounds aremethylbis(tallowamidoethyl)(2-hydroxyethyl)ammonium methylsulfate andmethylbis(hydrogenated tallowamidoethyl)(2-hydroxyethyl)ammoniummethylsulfate; these materials are available from Witco Chemical Companyunder the trade names Varisoft® 222 and Varisoft® 110, respectively.

Particularly preferred is N,N-di(tallowoyl-oxy-ethyl)-N,N-dimethylammonium chloride, where the tallow chains are at least partiallyunsaturated.

The level of unsaturation contained within the tallow, canola, or otherfatty acyl unit chain can be measured by the Iodine Value (IV) of thecorresponding fatty acid, which in the present case should preferably bein the range of from 5 to 100 with two categories of compounds beingdistinguished, having a IV below or above 25.

Indeed, for compounds having the formula:

derived from tallow fatty acids, when the Iodine Value is from 5 to 25,preferably 15 to 20, it has been found that a cis/trans isomer weightratio greater than about 30/70, preferably greater than about 50/50 andmore preferably greater than about 70/30 provides optimalconcentrability. For compounds of this type made from tallow fatty acidshaving a Iodine Value of above 25, the ratio of cis to trans isomers hasbeen found to be less critical unless very high concentrations areneeded.

Other suitable examples of fabric softener actives are derived fromfatty acyl groups wherein the terms “tallowyl” and canolyl” in the aboveexamples are replaced by the terms “cocoyl, palmyl, lauryl, oleyl,ricinoleyl, stearyl, palmityl,” which correspond to the triglyceridesource from which the fatty acyl units are derived. These alternativefatty acyl sources can comprise either fully saturated, or preferably atleast partly unsaturated chains.

As described herein before, R units are preferably methyl, however,suitable fabric softener actives are described by replacing the term“methyl” in the above examples in Table II with the units “ethyl,ethoxy, propyl, propoxy, isopropyl, butyl, isobutyl and t-butyl.

The counter ion, X, in the examples of Table II can be suitably replacedby bromide, methylsulfate, formate, sulfate, nitrate, and mixturesthereof. In fact, the anion, X, is merely present as a counterion of thepositively charged quaternary ammonium compounds. The scope of thisinvention is not considered limited to any particular anion.

For the preceding ester fabric softening agents, the pH of thecompositions herein is an important parameter of the present invention.Indeed, it influences the stability of the quaternary ammonium or amineprecursors compounds, especially in prolonged storage conditions.

The pH, as defined in the present context, is measured in the neatcompositions at 20° C. While these compositions are operable at pH ofless than about 6.0, for optimum hydrolytic stability of thesecompositions, the neat pH, measured in the above-mentioned conditions,must preferably be in the range of from about 2.0 to about 5, preferablyin the range of 2.5 to 4.5, preferably about 2.5 to about 3.5. The pH ofthese compositions herein can be regulated by the addition of a Bronstedacid.

Examples of suitable acids include the inorganic mineral acids,carboxylic acids, in particular the low molecular weight (C₁-C₅)carboxylic acids, and alkylsulfonic acids. Suitable inorganic acidsinclude HCl, H₂SO₄, HNO₃ and H₃PO₄. Suitable organic acids includeformic, acetic, citric, methylsulfonic and ethylsulfonic acid. Preferredacids are citric, hydrochloric, phosphoric, formic, methylsulfonic acid,and benzoic acids.

As used herein, when the diester is specified, it will include themonoester that is normally present in manufacture. For softening, underno/low detergent carry-over laundry conditions the percentage ofmonoester should be as low as possible, preferably no more than about2.5%. However, under high detergent carry-over conditions, somemonoester is preferred. The overall ratios of diester to monoester arefrom about 100:1 to about 2:1, preferably from about 50:1 to about 5:1,more preferably from about 13:1 to about 8:1. Under high detergentcarry-over conditions, the di/monoester ratio is preferably about 11:1.The level of monoester present can be controlled in the manufacturing ofthe softener compound.

Mixtures of actives of formula (1) and (2) may also be prepared.

2)-Still other suitable quaternary ammonium fabric softening compoundsfor use herein are cationic nitrogenous salts having two or more longchain acyclic aliphatic C₈-C₂₂ hydrocarbon groups or one said group andan arylalkyl group which can be used either alone or as part of amixture are selected from the group consisting of:

(i) acyclic quaternary ammonium salts having the formula:

wherein R⁴ is an acyclic aliphatic C₈-C₂₂ hydrocarbon group, R⁵ is aC₁-C₄ saturated alkyl or hydroxyalkyl group, R⁸ is selected from thegroup consisting of R⁴ and R⁵ groups, and A− is an anion defined asabove;

(ii) diamino alkoxylated quaternary ammonium salts having the formula:

wherein n is equal to 1 to about 5, and R¹, R², R⁵ and A⁻ are as definedabove;

(iii) mixtures thereof.

Examples of the above class cationic nitrogenous salts are thewell-known dialkyldi methylammonium salts such asditallowdimethylammonium chloride, ditallowdimethylammoniummethylsulfate, di(hydrogenatedtallow)dimethylammonium chloride,distearyidimethylammonium chloride, dibehenyidimethylammonium chloride.Di(hydrogenatedtallow)di methylammonium chloride andditallowdimethylammonium chloride are preferred. Examples ofcommercially available dialkyldimethyl ammonium salts usable in thepresent invention are di(hydrogenatedtallow)dimethylammonium chloride(trade name Adogen® 442), ditallowdimethylammonium chloride (trade nameAdogen® 470, Praepagen® 3445), distearyl dimethylammonium chloride(trade name Arosurf® TA-100), all available from Witco Chemical Company.Dibehenyldimethylammonium chloride is sold under the trade name KemamineQ-2802C by Humko Chemical Division of Witco Chemical Corporation.Dimethylstearylbenzyl ammonium chloride is sold under the trade namesVarisoft® SDC by Witco Chemical Company and Ammonyx® 490 by OnyxChemical Company.

B)-Amine Fabric Softening Active Compound

Suitable amine fabric softening compounds for use herein, which may bein amine form or cationic form are selected from:

(i)-Reaction products of higher fatty acids with a polyamine selectedfrom the group consisting of hydroxyalkylalkylenediamines anddialkylenetriamines and mixtures thereof. These reaction products aremixtures of several compounds in view of the multi-functional structureof the polyamines. The preferred Component (i) is a nitrogenous compoundselected from the group consisting of the reaction product mixtures orsome selected components of the mixtures. One preferred component (i) isa compound selected from the group consisting of substituted imidazolinecompounds having the formula:

wherein R⁷ is an acyclic aliphatic C₁₅-C₂₁ hydrocarbon group and R⁸ is adivalent C₁-C₃ alkylene group.

Component (i) materials are commercially available as: Mazamide® 6, soldby Mazer Chemicals, or Ceranine® HC, sold by Sandoz Colors & Chemicals;stearic hydroxyethyl imidazoline sold under the trade names of Alkazine®ST by Alkaril Chemicals, Inc., or Schercozoline® S by Scher Chemicals,Inc.; N,N″-ditallowalkoyidiethylenetriamine;1-tallowamidoethyl-2-tallowimidazoline (wherein in the precedingstructure R¹ is an aliphatic C₁₅-C₁₇ hydrocarbon group and R⁸ is adivalent ethylene group).

Certain of the Components (i) can also be first dispersed in a Bronstedacid dispersing aid having a pKa value of not greater than about 4;provided that the pH of the final composition is not greater than about6. Some preferred dispersing aids are hydrochloric acid, phosphoricacid, or methylsulfonic acid.

Both N,N″-ditallowalkoyldiethylenetriamine and1-tallow(amidoethyl)-2-tallowimidazoline are reaction products of tallowfatty acids and diethylenetriamine, and are precursors of the cationicfabric softening agent methyl-1-tallowamidoethyl-2-tallowimidazoliniummethylsulfate (see “Cationic Surface Active Agents as Fabric Softeners,”R. R. Egan, Journal of the American Oil Chemical' Society, January 1978,pages 118-121). N,N″-ditallow alkoyldiethylenetriamine and1-tallowamidoethyl-2-tallowimidazoline can be obtained from WitcoChemical Company as experimental chemicals.Methyl-1-tallowamidoethyl-2-tallowimidazolinium methylsulfate is sold byWitco Chemical Company under the tradename Varisoft® 475.

(ii)-softener having the formula:

wherein each R² is a C₁₋₆ alkylene group, preferably an ethylene group;and G is an oxygen atom or an —NR— group; and each R, R¹, R² and R⁵ havethe definitions given above and A⁻ has the definitions given above forX⁻.

An example of Compound (ii) is 1-oleylamidoethyl-2-oleylimidazoliniumchloride wherein R¹ is an acyclic aliphatic C₁₅-C₁₇ hydrocarbon group,R² is an ethylene group, G is a NH group, R⁵ is a methyl group and A⁻ isa chloride anion.

(iii)-softener having the formula:

wherein R, R¹, R², and A⁻ are defined as above.

An example of Compound (iii) is the compound having the formula:

wherein R¹ is derived from oleic acid.

Additional fabric softening agents useful herein are described in U.S.Pat. No. 4,661,269, issued Apr. 28, 1987, in the names of Toan Trinh,Errol H. Wahl, Donald M. Swartley, and Ronald L. Hemingway; U.S. Pat.No. 4,439,335, Burns, issued Mar. 27, 1984; and in U.S. Pat. No.3,861,870, Edwards and Diehl; U.S. Pat. No. 4,308,151, Cambre; U.S. Pat.No. 3,886,075, Bernardino; U.S. Pat. No. 4,233,164, Davis; U.S. Pat. No.4,401,578, Verbruggen; U.S. Pat. No. 3,974,076, Wiersema and Rieke; U.S.Pat. No. 4,237,016, Rudkin, Clint, and Young; and European PatentApplication publication No. 472,178, by Yamamura et al., all of saiddocuments being incorporated herein by reference.

Of course, the term “softening active” can also encompass mixedsoftening active agents.

Preferred among the classes of softener compounds disclosed hereinbefore are the diester or diamido quaternary ammonium fabric softeningactive compound (DEQA).

Another conventional optional ingredient of said liquid fabric softeningcompositions is a liquid carrier. Suitable liquid carriers are selectedfrom water, organic solvents and mixtures thereof. The liquid carrieremployed in the instant compositions is preferably at least primarilywater due to its low cost relative availability, safety, andenvironmental compatibility. The level of water in the liquid carrier ispreferably at least 50%, most preferably at least 60%, by weight of thecarrier. Mixtures of water and low molecular weight, e.g., <200, organicsolvent, e.g., lower alcohol such as ethanol, propanol, isopropanol orbutanol are useful as the carrier liquid. Low molecular weight alcoholsinclude monohydric, dihydric (glycol, etc.) trihydric (glycerol, etc.),and higher polyhydric (polyols) alcohols.

Optional Components

The composition may also optionally contain additional components suchas pH modifiers, perfumes, chelating agents, cationic surfactantconcentration aids, electrolyte concentration aids, thickeners,stabilisers, such as well known antioxidants and reductive agents, soilrelease polymers, emulsifiers, bacteriocides, colorants, preservatives,optical brighteners, anti ionisation agents, antifoam agents, enzymes,dye fixing agent such as polyquaternary ammonium compounds (e.g.Sandofix WE56 commercially available from Hoechst, or Rewin SFRcommercially available from CHT R. Beitlich), polyamino functionalpolymer such as disclosed in co-pending application EP 97201488.0,dispersible polyolefin such as Velustrol® as disclosed in co-pendingapplication PCT/US 97/01644, and the like. A typical amount of suchoptional components will be from 0% to 15% by weight.

Perfume

The word perfume encompasses individual perfume components andcompositions of perfume components. Selection of any perfume is basedsolely on aesthetic considerations.

Perfume, in the sense of perfume components or compositions of perfumecomponents, can be any odoriferous materials or any materials which actas a malodour counteractent. The perfume will most often be liquid atambient temperatures, but also can be liquified solid such as thevarious camphoraceous perfumes known in the art. The perfume can berelatively simple in composition or can comprise highly sophisticated,compact mixtures of natural or synthetic chemical components, all chosento provide any desired odour.

Useful perfumes are those odorous materials that deposit on fabricsduring the laundry process and are detectable by people with normalolfactory sensity. Many of the perfume ingredients along with their odorcorrector and their physical and chemical properties are given in“Perfume and Flavor chemicals (aroma chemicals)”, Stephen Arctender,Vols. I and II, Aurthor, Montclair, H. J. and the Merck Index, 8thEdition, Merck & Co., Inc. Rahway, N.J. Perfume components andcompositions can also be found in the art, e.g. U.S. Pat. Nos.4,145,184, 4,152,272, 4,209,417 or 4,515,705.

A wide variety of chemicals are known for perfume use includingmaterials such as aldehydes, ketones, esters and the like. Morecommonly, naturally occurring plant and animal oils and exudatescomprising complex mixtures of various chemical components are known foruse as perfume, and such materials can be used herein. Typical perfumescan comprise e.g. woody/earthy bases containing exotic materials such assandalwood oil, civet and patchouli oil. The perfume also can be of alight floral fragrance e.g. rose or violet extract. Further the perfumecan be formulated to provide desirable fruity odours e.g. lime, lemon ororange.

Particular examples of useful perfume components and compositions areanetole, benzaldehyde, benzyl acetate, benzyl alcohol, benzyl formate,iso-bornyl acetate, camphene, cis-citral (neral), citronellal,citronellol, citronellyl acetate, paracymene, decanal, dihydrolinalool,dihydromyrcenol, dimethyl phenyl carbinol, eucalyptol, geranial,geraniol, geranyl acetate, geranyl nitrile, cis-3-hexenyl acetate,hydroxycitronellal, d-limonene, linalool, linalool oxide, linalylacetate, linalyl propionate, methyl anthranilate, alpha-methyl ionone,methyl nonyl acetaldehyde, methyl phenyl carbinyl acetate, laevo-menthylacetate, menthone, iso-menthone, myrcene, myrcenyl acetate, myrcenol,nerol, neryl acetate, nonyl acetate, phenyl ethyl alcohol, alpha-pinene,beta-pinene, gamma-terpinene, alpha-terpineol, beta-terpineol, terpinylacetate, vertenex (para-tertiary-butyl cyclohexyl acetate), amylcinnamic aldehyde, iso-amyl salicylate, beta-caryophyllene, cedrene,cinnamic alcohol, couramin, dimethyl benzyl carbinyl acetate, ethylvanillin, eugenol, iso-eugenol, flor acetate, heliotrophine,3-cis-hexenyl salicylate, hexyl salicylate, lilial(para-tertiarybutyl-alpha-methyl hydrocinnamic aldehyde), gamma-methylionone, nerolidol, patchouli alcohol, phenyl hexanol, beta-selinene,trichloromethyl phenyl carbinyl acetate, triethyl citrate, vanillin,veratraldehyde, alpha-cedrene, beta-cedrene, C15H24sesquiterpenes,benzophenone, benzyl salicylate, ethylene brassylate, galaxolide(1,3,4,6,7,8-hexahydro-4,6,6,7,8,8,-hexamethyl-cyclo-penta-gamma-2-benzopyran),hexyl cinnamic aIdehyde, lyral (4-(4-hydroxy4-methylpentyl)-3-cyclohexene-10-carboxaldehyde), methyl cedrylone, methyldihydro jasmonate, methyl-beta-naphthyl ketone, musk ambrette, muskidanone, musk ketone, musk tibetine, musk xylol, aurantiol andphenylethyl phenyl acetate.

Perfume can be present at a level of from 0% to 10%, preferably from0.1% to 5%, and more preferably from 0.2% to 3%, by weight of thefinished composition. Fabric softener compositions of the presentinvention provide improved fabric perfume deposition.

Additional Components

Concentration Aids

Concentrated compositions of the present invention may require organicand/or inorganic concentration aids to go to even higher concentrationsand/or to meet higher stability standards depending on the otheringredients. Surfactant concentration aids are typically selected fromthe group consisting of single long chain alkyl cationic surfactants;nonionic surfactants; amine oxides; fatty acids; or mixtures thereof,typically used at a level of from 0 to 15% of the composition. Inorganicviscosity/dispersibility control agents which can also act like oraugment the effect of the surfactant concentration aids, includewater-soluble, ionizable salts which can also optionally be incorporatedinto the compositions of the present invention. A wide variety ofionizable salts can be used. Examples of suitable salts are the halidesof the Group IA and IIA metals of the Periodic Table of the Elements,e.g., calcium chloride, magnesium chloride, sodium chloride, potassiumbromide, and lithium chloride. The ionizable salts are particularlyuseful during the process of mixing the ingredients to make thecompositions herein, and later to obtain the desired viscosity. Theamount of ionizable salts used depends on the amount of activeingredients used in the compositions and can be adjusted according tothe desires of the formulator. Typical levels of salts used to controlthe composition viscosity are from about 20 to about 20,000 parts permillion (ppm), preferably from about 20 to about 11,000 ppm, by weightof the composition.

Alkylene polyammonium salts can be incorporated into the composition togive viscosity control in addition to or in place of the water-soluble,ionizable salts above. In addition, these agents can act as scavengers,forming ion pairs with anionic detergent carried over from the mainwash, in the rinse, and on the fabrics, and may improve softnessperformance. These agents may stabilize the viscosity over a broaderrange of temperature, especially at low temperatures, compared to theinorganic electrolytes.

Specific examples of alkylene polyammonium salts include l-lysinemonohydrochloride and 1,5-diammonium 2-methyl pentane dihydrochloride.

Enzymes

The compositions herein can optionally employ one or more enzymes suchas lipases, proteases, cellulase, amylases and peroxidases. A preferredenzyme for use herein is a cellulase enzyme. Indeed, this type of enzymewill further provide a color care benefit to the treated fabric.Cellulases usable herein include both bacterial and fungal types,preferably having a pH optimum between 5 and 9.5. U.S. Pat. No.4,435,307 discloses suitable fungal cellulases from Humicola insolens orHumicola strain DSM1800 or a cellulase 212-producing fungus belonging tothe genus Aeromonas, and cellulase extracted from the hepatopancreas ofa marine mollusk, Dolabella Auncula Solander. Suitable cellulases arealso disclosed in GB-A-2.075.028; GB-A-2.095.275 and DE-OS-2.247.832.CAREZYME® and CELLUZYME® (Novo) are especially useful. Other suitablecellulases are also disclosed in WO 91/17243 to Novo, WO 96/34092, WO96/34945 and EP-A-0,739,982. In practical terms for current commercialpreparations, typical amounts are up to 5 mg by weight, more typically0.01 mg to 3 mg, of active enzyme per gram of the detergent composition.Stated otherwise, the compositions herein will typically comprise from0.001% to 5%, preferably 0.01%-1% by weight of a commercial enzymepreparation. In the particular cases where activity of the enzymepreparation can be defined otherwise such as with cellulases,corresponding activity units are preferred (e.g. CEVU or cellulaseEquivalent Viscosity Units). For instance, the compositions of thepresent invention can contain cellulase enzymes at a level equivalent toan activity from about 0.5 to 1000 CEVU/gram of composition. Cellulaseenzyme preparations used for the purpose of formulating the compositionsof this invention typically have an activity comprised between 1,000 and10,000 CEVU/gram in liquid form, around 1,000 CEVU/gram in solid form.

Soil Release Agents

In the present invention, an optional soil release agent can be added.The addition of the soil release agent can occur in combination with thepremix, in combination with the acid/water seat, before or afterelectrolyte addition, or after the final composition is made. Thesoftening composition prepared by the process of the present inventionherein can contain from 0% to 10%, preferably from 0.2% to 5%, of a soilrelease agent. Preferably, such a soil release agent is a polymer.

Any polymeric soil release agent known to those skilled in the art canoptionally be employed in the compositions of this invention. Polymericsoil release agents are characterized by having both hydrophilicsegments, to hydrophilize the surface of hydrophobic fibers, such aspolyester and nylon, and hydrophobic segments, to deposit uponhydrophobic fibers and remain adhered thereto through completion ofwashing and rinsing cycles and, thus, serve as an anchor for thehydrophilic segments. This can enable stains occurring subsequent totreatment with the soil release agent to be more easily cleaned in laterwashing procedures.

If utilised, soil release agents will generally comprise from about0.01% to about 10.0%, by weight, of the detergent compositions herein,typically from about 0.1% to about 5%, preferably from about 0.2% toabout 3.0%.

The following, all included herein by reference, describe soil releasepolymers suitable for use in the present invention. U.S. Pat. No.3,959,230 Hays, issued May 25, 1976; U.S. Pat. No. 3,893,929 Basadur,issued Jul. 8, 1975; U.S. Pat. No. 4,000,093, Nicol, et al., issued Dec.28, 1976; U.S. Pat. No. 4,702,857 Gosselink, issued Oct. 27, 1987; U.S.Pat. No. 4,968,451, Scheibel et al., issued Nov. 6; U.S. Pat. No.4,702,857, Gosselink, issued Oct. 27, 1987; U.S. Pat. No. 4,711,730,Gosselink et al., issued Dec. 8, 1987; U.S. Pat. No. 4,721,580,Gosselink, issued Jan. 26, 1988; U.S. Pat. No. 4,877,896, Maldonado etal, issued Oct. 31, 1989; U.S. Pat. No. 4,956,447, Gosselink et al.,issued Sep. 11, 1990; U.S. Pat. No. 5,415,807 Gosselink et al., issuedMay 16, 1995; European Patent Application 0 219 048, published Apr. 22,1987 by Kud, et al.

Further suitable soil release agents are described in U.S. Pat. No.4,201,824, Violland et al.; U.S. Pat. No. 4,240,918 Lagasse et al.; U.S.Pat. No. 4,525,524 Tung et al.; U.S. Pat. No. 4,579,681, Ruppert et al.;U.S. Pat. No. 4,240,918; U.S. Pat. No. 4,787,989; U.S. Pat. No.4,525,524; EP 279,134 A, 1988, to Rhone-Poulenc Chemie; EP 457,205 A toBASF (1991); and DE 2,335,044 to Unilever N. V., 1974 all incorporatedherein by reference.

Commercially available soil release agents include the METOLOSE SM100,METOLOSE SM200 manufactured by Shin-etsu Kagaku Kogyo K.K., SOKALAN typeof material, e.g., SOKALAN HP-22, available from BASF (Germany), ZELCON5126 (from Dupont) and MILEASE T (from ICI). These soil release agentscan also act as scum dispersants.

Stabilizers

Stabilizers can be present in the compositions of the present invention.The term “stabilizer,” as used herein, includes antioxidants andreductive agents. These agents are present at a level of from 0% toabout 2%, preferably from about 0.01% to about 0.2%, more preferablyfrom about 0.035% to about 0.1% for antioxidants, and more preferablyfrom about 0.01% to about 0.2% for reductive agents. These assure goododor stability under long term storage conditions for the compositionsand compounds stored in molten form. The use of antioxidants andreductive agent stabilizers is especially critical for low scentproducts (low perfume).

Examples of antioxidants that can be added to the compositions of thisinvention include a mixture of ascorbic acid, ascorbic palmitate, propylgallate, available from Eastman Chemical Products, Inc., under the tradenames Tenox® PG and Tenox S-1; a mixture of BHT (butylatedhydroxytoluene), BHA (butylated hydroxyanisole), propyl gallate, andcitric acid, available from Eastman Chemical Products, Inc., under thetrade name Tenox-6; butylated hydroxytoluene, available from UOP ProcessDivision under the trade name Sustane® BHT; tertiary butylhydroquinone,Eastman Chemical Products, Inc., as Tenox TBHQ; natural tocopherols,Eastman Chemical Products, Inc., as Tenox GT-1/GT-2; and butylatedhydroxyanisole, Eastman Chemical Products, Inc., as BHA; long chainesters (C8-C22) of gallic acid, e.g., dodecyl gallate; Irganox® 1010;Irganox® 1035; Irganox® B 1171; Irganox® 1425; Irganox® 3114; Irganox®3125; and mixtures thereof; preferably Irganox® 3125, Irganox® 1425,Irganox® 3114, and mixtures thereof; more preferably Irganox® 3125 aloneor mixed with citric acid and/or other chelators such as isopropylcitrate, Dequest® 2010, available from Monsanto with a chemical name of1-hydroxyethylidene-1, 1-diphosphonic acid (etidronic acid), and Tiron®,available from Kodak with a chemical name of4,5-dihydroxy-m-benzene-sulfonic acid/sodium salt, EDDS, and DTPA®,available from Aldrich with a chemical name ofdiethylenetriaminepentaacetic acid. The chemical names and CAS numbersfor some of the above stabilizers are listed in Table II below.

TABLE II Chemical Name used in Code of Federal Antioxidant CAS No.Regulations Irganox ® 1010 6683-19-8 Tetrakis(methylene(3,5-di-tert-butyl-4 hydroxyhydrocinnamate)) methane Irganox ®1035 41484-35-9 Thiodiethylene bis(3,5-di-tert-butyl-4-hydroxyhydrocinnamate Irganox ® 1098 23128-74-7 N,N′-Hexamethylenebis(3,5-di-tert-butyl-4- hydroxyhydrocinnamamide Irganox ® B117131570-04-4 23128-74-7 1:1 Blend of Irganox ® 1098 and Irgafos ® 168Irganox ® 1425 65140-91-2 Calcium bis(monoethyl(3,5-di-tert-butyl-4-hydroxybenzyl)phosphonate) Irganox ® 3114 65140-91-2 Calciumbis(monoethyl(3,5-di-tert-butyl-4- hydroxybenzyl)phosphonate) Irganox ®3125 34137-09-2 3,5-Di-tert-butyl-4-hydroxy-hydrocinnamic acid triesterwith 1,3,5-tris(2-hydroxyethyl)-S- triazine-2,4,6-(1H, 3H, 5H)-trioneIrgafos ® 168 31570-04-4 Tris(2,4-di-tert-butyl-phenyl)phosphite

Examples of reductive agents include sodium borohydride, hypophosphorousacid, Irgafos® 168, and mixtures thereof.

Process

The process for making a liquid fabric softening composition accordingto the invention comprises the steps of:

a)-mixing and heating the fabric softener active and optional additivesto form a melt;

b)-dispersing the melt in water;

c)-cooling the resulting dispersion to below the Krafft temperature ofthe softener active before adding a dye and a nonionic stabilisingagent.

By Krafft temperature, it is meant the temperature at which thesolubility of the surfactant becomes equal to the critical micelleconcentration (CMC), the CMC being defined in M.J ROSEN, Surfactants andinterfacial phenomena, 1988, p.215.

Typically, the product is cooled to below 25° C.

Preferably, the mixing of Step a of the invention process is typicallymade with a marine type mixing impeller for 2 minutes. The dispersion ofstep b of the process is conveniently made using a flat blade turbineimpeller at 100 rpm for 10 minutes, the viscosity being measured using aBrookfield LVT viscositymeter.

The cooling step as defined under c) is conveniently made using a plateheat exchanger (α level) at about 30 ton/hour using a positivedisplacement pump.

The dye and nonionic stabilising agent is mixed in the cooled productusing a marine type mixing impeller.

In another aspect of the invention, there is provided the use of saidnonionic ethoxylated stabilising agent in liquid fabric softeningcompositions as a freeze-thaw recovery agent.

By “freeze-thaw recovery agent”, it is meant that the resulting productstill exhibits effective dispersibility property after prolongedexposure to freeze-thaw temperatures.

Still in another aspect, the present invention encompasses the use of anonionic alkoxylated stabilising agent to homogenise the dye in liquidfabric softening compositions.

The invention is illustrated in the following non limiting examples, inwhich all percentages are on a weight basis unless otherwise stated.

In the examples, the abbreviated component identifications have thefollowing meanings:

DEQA: Di-(tallowyl-oxy-ethyl)dimethyl ammonium chloride

DTDMAC: Ditallow dimethylammonium chloride

Fatty acid: Tallow fatty acid IV=18

Electrolyte: Calcium chloride

PEG: Polyethylene Glycol 4000

IPA: Isopropyl alcohol

Nonionic: Marlipal 24/100 commercially available from Huls

EXAMPLE

The following resulting compositions were prepared in accordance withthe process invention:

Component A B C D E DTDMAC — — — — 4.5 DEQA 2.6 5.1 6.35 4.12 — (85%IPA) Fatty acid — — — 0.2 — Nonionic 0.1 0.25 0.3 0.35 0.25Hydrochloride 0.02 0.02 0.02 0.02 0.02 acid Perfume 0.10 0.15 0.21 0.280.25 Silicone 0.005 0.005 0.005 0.005 0.01 antifoam Dye (ppm) 10 10 5 510 Water and minors to balance to 100

What is claimed is:
 1. A process for making a liquid fabric softeningcomposition which comprises the steps of: a)-mixing and heating thefabric softener active and optional additives to form a melt;b)-dispersing the melt in water; c)-cooling the resulting dispersion tobelow the Krafft temperature of the softener active before adding a dyeand a nonionic, alkoxylated stabilising agent.
 2. A process according toclaim 1, wherein said nonionic stabilising agent is selected from:R²—Y—(C₂H₄O)_(z)—C₂H₄OH wherein R² is selected from the group consistingof primary, secondary and branched chain alkyl and/or acyl hydrocarbylgroups; primary, secondary and branched chain alkenyl hydrocarbylgroups; and primary, secondary and branched chain alkyl- andalkenyl-substituted phenolic hydrocarbyl groups; wherein Y is —O—,—C(O)O—, —C(O)N(R)—, or —C(O)N(R)R—, and wherein z is at least
 5. 3. Aprocess according to claim 2, wherein said hydrocarbyl group of thenonionic stabilising agent has a chain length of from 8 to 20 carbonatoms.
 4. A process according to claim 1, wherein said nonionicstabilising agent is selected from the group consisting ofstraight-chain primary alcohol alkoxylates, straight-chain secondaryalcohol alkoxylates, alkyl phenol alkoxylates, olefinic alkoxylatesbranched chain alkoxylates and mixtures thereof.
 5. A process accordingto claim 1, wherein said nonionic alkoxylated stabilising agent isincorporated into the cold finished fabric softening composition at alevel of 0.05% to 5% by weight of the liquid softening composition.
 6. Aprocess according to claim 1, wherein a perfume is added to the coldfinished product.
 7. A process according to claim 3, wherein saidhydrocarbyl group of the nonionic stabilising agent has a chain lengthof from 10 to 18 carbon atoms.